Roth was the one who told police on July 28 that his father, Raymond Roth, 47, had gone for an ocean swim that afternoon and never returned.

"I was just so mad," the son said. He remembered thinking, "How could you leave me at the beach that day? I thought you were dead."

Raymond Roth, an unemployed telecommunications manager, wasn't seen until last Wednesday when an officer in Santee, S.C., ticketed him for speeding. Police believe he initially fled to Orlando, Fla., where he has a time-share in a resort.

The South Carolina cop let him go because it's not illegal to be a missing person, police said, and investigators in New York say he promised police here that he'd meet with them upon his return to Long Island.

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The investigation into the disappearance is continuing. Electronic-crime experts are examining a computer and a monitor taken from Roth's home, said Capt. Bruce Marx of the State Park Police, which has jurisdiction over the beach.

Marx said he hasn't heard from Raymond Roth since Thursday afternoon, when Roth called, saying he was in the Washington, D.C., area and headed home.

He'd agreed to meet with park police late that night but never showed up, Marx said. His current whereabouts is unknown.

Wife of missing swimmer speaks out
Evana Roth, wife of Raymond Roth, says she was planning for a funeral when she found suspicious e-mails from her husband. Videojournalist: Jim Staubitser (August 3, 2012)

Evana Roth, 45, a receptionist at a doctor's office, told reporters Friday that she believed her husband of 12 years had faked his death because he was looking for a way out of financial woes. Raymond Roth had recently lost his job and put the Massapequa house up for sale shortly before he went missing.

She released emails that she claimed was evidence that her husband and stepson were plotting to fake his death. The messages, which start the day before the disappearance, discuss getting cash for a "trip" and instruct the son on when and where to telephone him at "the resort."

Jonathan Roth said he did not know about the emails and said he never received them. "It's all so awkward; it doesn't look right at all," Roth said, adding that he had three passwords protecting his computer and email.

The son recalled the day of the disappearance -- when he and his father went to the beach. Lying on a towel at Field 6, Jonathan Roth said he played a game on his iPhone and last saw his father in the water up to his neck. About 15 minutes later, he recalled, he couldn't see his father anymore. He said he panicked and called his stepmother and his father's brother, Bob Roth.

"I ran the length of a football field to find a lifeguard. I was freaking out," said Roth, a former Marine who admitted being forced to leave the corps for underage drinking.

While he's not spoken to his father since the disappearance, he said Raymond Roth has called him five times and left two threatening voice mails.

Police and prosecutors would not confirm the voice mails on Sunday.

Roth, who previously lived with his stepmother and father, said he's currently unemployed and living in a hotel in Long Island.